// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CHROME_BROWSER_CHROME_PLUGIN_BROWSING_CONTEXT_H_
#define CHROME_BROWSER_CHROME_PLUGIN_BROWSING_CONTEXT_H_

#include <map>

#include "base/id_map.h"
#include "chrome/common/chrome_plugin_api.h"
#include "chrome/common/notification_observer.h"

class URLRequestContext;

// This class manages the mapping between CPBrowsingContexts and
// URLRequestContexts.  It observes when URLRequestContexts go away, and
// invalidates the corresponding CPBrowsingContexts.  CPBrowsingContexts can be
// associated with other data as well, so there can be multiple ones referring
// to a given URLRequestContext.
// Note: This class should be used on the IO thread only.
class CPBrowsingContextManager : public NotificationObserver {
 public:
  static CPBrowsingContextManager* Instance();

  // Note: don't call these directly - use Instance() above.  They are public
  // so Singleton can access them.
  CPBrowsingContextManager();
  ~CPBrowsingContextManager();

  // Generate a new unique CPBrowsingContext ID from the given
  // URLRequestContext.  Multiple CPBrowsingContexts can map to the same
  // URLRequestContext.
  CPBrowsingContext Allocate(URLRequestContext* context);

  // Return the URLRequestContext that this CPBrowsingContext refers to, or NULL
  // if not found.
  URLRequestContext* ToURLRequestContext(CPBrowsingContext id);

  // Return a CPBrowsingContext ID that corresponds to the given
  // URLRequestContext. This function differs from Allocate in that calling
  // this multiple times with the same argument gives the same ID.
  CPBrowsingContext Lookup(URLRequestContext* context);

 private:
  // NotificationObserver
  virtual void Observe(NotificationType type,
                       const NotificationSource& source,
                       const NotificationDetails& details);

  typedef IDMap<URLRequestContext> Map;
  typedef std::map<URLRequestContext*, CPBrowsingContext> ReverseMap;

  Map map_;  // map of CPBrowsingContext -> URLRequestContext
  ReverseMap reverse_map_;  // map of URLRequestContext -> CPBrowsingContext
};

#endif  // CHROME_BROWSER_CHROME_PLUGIN_BROWSING_CONTEXT_H_